Investigating the Effect of Heavy Airplanes on the Reflective Cracking of Airport Composite Pavements Using Extended Finite Elements Method (XFEM)

In this study, the effects of two typical commercial heavy airplanes, namely airbus AA380-800 and Boeing B747-400ER, on the potential of reflective crack propagation in composite pavement have been investigated. The axles of the airplanes were positioned at different longitudinal and transverse distances from the center of crack and the stress intensity factors, and tensile strain at the tip of crack in asphaltic layer were determined and compared. Modeling and analysis were performed using extended 3D finite elements method. The asphaltic layer was assumed to behave as a viscoelastic material and the underlying layers were assumed to be linear elastic. Results show that higher maximum stress intensity factor in mode 1 is generated under Boeing airplane loading than airbus, and those in mode 2 and 3, are higher for airbus than Boeing. Results also reveal that by moving the center of axles along the longitudinal joint, the maximum tensile strain at the tip of crack decreases, such that 42.87% reduction for airbus and 23.89% reduction for Boeing airplane is obtained, in comparison to the loading at the center. By moving the center of axles in transverse direction, the maximum tensile strain at the tip of crack increases by 26.73 and 17.93%, in comparison with the load at the center for airbus and Boeing airplane, respectively.